As part of a previous funded RCMI cycle, an Optical Imaging Facility was established at UCC during the fall of 1999. The first major equipment acquired for this facility was a sensitive microscope-based system that allows the assessment of cellular responses such as calcium signaling with fast temporal resolution. The system also allows the spatial assessment of this functional variable, which means that an investigator is able to identify the heterogeneity of calcium signal responses in neighboring groups of cells. This proposal requests funds to continue providing technical support for this time-lapsed cell imaging system and the maintenance of its sophisticated equipment. Due to the nature of experiments, this particular microscope setup is a highly dedicated system. Therefore, in order to provide technical support for other microscope-based applications, this proposal is also requesting funds to support the integration of an immunocytochemistry laboratory into the Optical Imaging Facility. The immunocytochemistry laboratory specializes in the qualitative identification and localization of cells bearing selective markers by employing specific antibodies to these molecules. The referenced laboratory was organized in 1999 through the initiatives of Drs. Serguei Skatchkov and Misty Eaton, who have been successfully using this technology in the experimental design of their projects. In 1997, Dr. Skatchkov, thanks to an earlier RCMI supported Methodology Transfer Program, received training in a leading immunocytochemistry laboratory at Humboldt University, Berlin. The immunocytochemistry laboratory equipment includes an upright fluorescence microscope and a high-resolution digital camera. Immunocytochemistry data obtained in this laboratory has been published in peer-reviewed journals and presented in local and national symposiums. Currently, there are several projects that will benefit directly from the service provided by this microscope-based Iechnology. Therefore, the aims of the Optical Imaging Facility are: 1. To provide technical support for the time and spatial resolution imaging systems. 2. To integrate an immunocytochemistry laboratory into the Optical Imaging Facility. 3. To disseminate in our academic community the capabilities of our facility. 4. To work on the submission of a grant for a confocal microscope. The continued support of the Optical Imaging Facility will constitute an asset for the Cell and Molecular Biology Center since it will contribute to enhance the productivity of its current participants and will constitute an attractive research resource for potential new investigators/collaborators. The immunocytochemisty capabilities at the Optical Imaging Facility will complement our existing imaging platform that is configured for the rapid acquisition and analysis of fluorescently tagged reporters of intracellular calcium.